No, but why would you want to duplicate a constant array anyway? Sometimes for matrix operations there's a need/desire to do so, but generally a temporary via repmat() or some other technique would be more reasonable than just holding multiple copies of the same array.

B1(1) refers to a single array location whereas the rhs is an array. "Can't put 5-lbs of 'taters in a 1-lb tote" to use the E TN vernacular.